Obese Drivers May Be More Likely to Die in Car Crashes

TUESDAY, Jan. 22 (HealthDay News) -- Obese drivers are up to 80
percent more likely to die in a car crash than normal-weight
drivers, a new study finds.

Car designers may need to take heavier drivers into
consideration to keep them safer, the researchers said.

"This study highlights yet another negative consequence of obesity," said study co-author Thomas Rice, a research epidemiologist with the University of California, Berkeley's Safe Transportation Research & Education Center.

"Our findings suggest two things: first, that there is something about obese vehicle occupants that causes poorer outcomes. That thing is probably a higher prevalence of comorbidities -- other health conditions -- related to obesity that inhibit survival and recovery from severe injury," he said.

Second, earlier research has shown that the proper interaction
between seat belts and the human body is inhibited in the obese,
Rice said.

"Specifically, the lap belt is prevented from engaging the pelvis due to excess body fat. It is this engagement between lap belt and pelvis that impedes the forward motion of occupants during frontal collisions," he said.

Rice stressed the importance of proper seat belt use, especially
among the obese. "It is critical that the lap belt be positioned as
low as possible on the lap and as close to one's pelvis as
possible," he said.

The report was published in the Jan. 21 online edition of the
Emergency Medicine Journal.

For the study, Rice and Dr. Motao Zhu, from the department of
epidemiology and Injury Control Research Center at the University
of West Virginia, used fatality data from the U.S. National Highway
Traffic Safety Administration for 1996 to 2008.

During that time, details of more than 57,000 car accidents were
documented. Rice and Zhu looked specifically for accidents
involving two cars resulting in a death. They refined their search
further and included only accidents involving cars of similar size
and type. In all, their final pool included more than 3,400 pairs
of drivers.

Obesity was determined by body mass index (BMI), a measurement
that takes both height and weight into account.

As the level of obesity increased, so did the odds of dying in
the crash. Compared to normal-weight drivers, those at the lowest
level of obesity were 21 percent more likely to die, those at the
next level were 51 percent more likely to die and those who were
most obese were 80 percent more likely to die, Rice and Zhu
found.

Obese women had a greater risk of dying than obese men, the
researchers noted.

In addition, underweight men were slightly more likely to die in
a crash than normal-weight drivers, the study found.

These risks remained even for drivers wearing seat belts and
even when the airbag deployed, the authors noted.

Car design may have to be adapted to reduce the risk to these
drivers, Rice and Zhu add, especially in light of the U.S. obesity
epidemic.

"It may be the case that passenger vehicles are well designed to protect normal-weight vehicle occupants but are deficient in protecting overweight or obese occupants," they wrote in their study.

Commenting on the findings, Dr. David Katz, director of the Yale
University Prevention Research Center, said: "We have a serious and
pernicious problem of anti-obesity bias in the United States.
Efforts to address that may at times invite us to pretend that size
doesn't matter, but, in fact, it does."

The world around us has been built to accommodate prevailing
norms of height, weight, he noted. "It just stands to reason that
safety systems such as those in cars, designed for people of a
certain average size, may serve a population of a larger average
size less well," Katz said.

That may be what's behind the new findings, he said, but it also
could be that obesity-related illnesses affect recovery from
trauma.

"But minimally, [the findings] appear to mean that in car crashes, size does matter, because it affects outcome. How, why and what we can do about it now become the important questions," Katz said.

Although the study found an association between obesity and
death rates in car crashes, it did not establish a cause-and-effect
relationship.

Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.